Thermal history evaluation of low-grade altered or metamorphic rocks using thermometer based on geological kinetic indicator -estimation of duration of thermal event-

基于地质动力学指标的温度计对低品位蚀变或变质岩的热历史评估-热事件持续时间的估计-

• 批准号: 11554019
• 负责人: OHIRA Hiroto
• 金额: $ 5.06万
• 依托单位: Shimane University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11554019/
• 关键词: fission track; basin; apatite; thermal history; zircon; Songliao Basin; annealing; oil; 熱履歴; 古地温勾配; 大慶油田; 閉鎖温度; 年代測定; 隠岐島後

Thermal history evaluation using fission tack annealing kinetics was applied for the Songliao Basin. Firstly, to constrain the maximum deposition age of the Cretaceous Strata, zircon and apatite fission track dating and fission track length measurement have been carried out for the sedimentary rocks collected from the drilling well in the central depression area, western flank area and surrounding areas. Zircon and apatite FT ages and FT lengths for Cretaceous Strata suggest that the source region has a fairly homogeneous cooling history at 120-100 Ma. This means that the volcanic rocks in the Dahinganling Mountains near the basin were eroded soon after their deposition and were reworked toward the Songliao Basin. While, apatites from deep core sample at depression part of the basin show severely annealed ages. Secondary, to estimate post-Cretaceous paleo-geotherm, the younging trend of apatites from each depth were analyzed according to the following step. (1) Making burial history fo … More r each core sample using Sclater and Cristie's compaction model, (2) supposing the hypothetical constant paleo-geothermal gradients, (3) estimate younging trends for each sample's thermal histories using forward modeling technique, (4) statistical check between the predicted FT younging trend and observed younging trend. As a result, the good fitted paleo-geotherm was estimated for 40-45 ℃/km and several tens of Myrs was estimated for the duration of the geotherm. On the other hand, the methylphenanthrene index (MPI), wide-range maturation indicator, was analyzed especially from oil basin at green-tuff region in Japan to know the variation of MPI and its relation to Ro %. For all rock samples, the MPI showed increase from 0.7 to 4.2 in the mature zone (%Ro=0.5-1.9 and decrease from 4.2 to 1.3 in the over-mature zone %Ro=1.9-4.5. The upper slope in these trends was discussed by means of geochemical kinetics, suggesting that the MPI change depend on production of intermediate MPI and the methyl-shift from alpha-isomer to beta isomer. Less

应用裂变tack退火动力学方法对松辽盆地进行了热史评价。首先，为约束白垩系地层的最大沉积年龄，对中部坳陷区、西翼区及周边钻井采集的沉积岩进行了锆石和磷灰石裂变径迹定年和裂变径迹长度测量。白垩纪地层锆石和磷灰石的FT年龄和FT长度表明，源区在120 ~ 100 Ma具有相当均匀的冷却历史。这说明盆地附近的大兴安岭火山岩在沉积后不久就受到了侵蚀，并向松辽盆地进行了再加工。而盆地凹陷部分深层岩心磷灰石则表现出严重的退火年龄。其次，对各深度磷灰石的年轻化趋势进行了分析，以估计白垩纪后的古地热。(1)利用Sclater和Cristie的压实模型对每个岩心样品进行埋藏史研究；(2)假设古地温梯度恒定；(3)利用正演模拟技术估计每个岩心样品的热史年轻化趋势；(4)对预测的FT年轻化趋势与观测的年轻化趋势进行统计检验。结果表明，拟合良好的古地热温度为40 ~ 45℃/km，地热持续时间估计为几十Myrs。另一方面，以日本绿凝灰岩区含油盆地为研究对象，分析了大范围成熟度指标甲基菲指数（MPI）的变化及其与Ro %的关系。所有岩石样品的MPI在成熟区（%Ro=0.5 ~ 1.9）由0.7增大到4.2，在过成熟区（%Ro= 1.9 ~ 4.5）由4.2减小到1.3。用地球化学动力学的方法讨论了这些趋势的上斜率，表明MPI的变化取决于中间MPI的产生和从α -异构体到β -异构体的甲基转移。少

项目成果

Himeno O., Ohira H., Zhaojun L., Xue J. and Watanabe K.: "Post-Cretaceous palaeogeotherm and deposition age in the Songliao Basin, NE China inferred from fission track thermal history analysis"Fission track news letter. 13. 21-23 (2000)

Himeno O.、Ohira H.、Zhaojun L.、Xue J. 和 Watanabe K.：“根据裂变径迹热历史分析推断中国东北松辽盆地的后白垩纪古地温和沉积年龄”裂变径迹新闻通讯。

Himeno O., Ohira H., Wtanabe K.: "Cretaceous deposition age and paleogeotherm in the Songliao Basin, Northeast China inferred from fission track thermal history analysis (in press)"International Geology Review. (2002)

Himeno O.，Ohira H.，Wtanabe K.：“从裂变径迹热历史分析推断中国东北松辽盆地的白垩纪沉积年龄和古地温（正在出版）”国际地质评论。

Sampei, Y. and Matsumoto, E: "C/N ratios in a sediment core from Nakaumi lagoon, southwest Japan -usefulness as an organic source indicator-"Geochem. Jour. 35. 189-205 (2001)

Sampei, Y. 和 Matsumoto, E：“日本西南部 Nakaumi 泻湖沉积物核心中的 C/N 比 - 作为有机源指标的有用性 -”Geochem。

姫野修,大平寛人 ほか: "フィッショントラック熱史解析による中国東北地方松遼盆地の堆積時代と古地温勾配"フィッショントラック・ニュースレター. 13巻. 21-24 (2000)

Osamu Himeno，Hiroto Ohira等：“中国东北松辽盆地的沉积年龄和古地温梯度的裂变径迹热历史分析”裂变径迹通讯Vol. 13. 21-24 (2000)。

Sampei, Y., Matsumoto, E: "C/N ratios in a sediment core from Nakaumi lagoon, southwest Japan -usefulness as an organic source indicator -"Geochem. Jour. 35. 189-205 (2001)

Sampei, Y., Matsumoto, E：“日本西南部 Nakaumi 泻湖沉积物核心中的 C/N 比率 - 作为有机源指标的有用性 -”Geochem。